This invention relates to innovations and improvements in hand tools which in part are similar to so-called "pliers" and in part are similar to wrenches. More particularly the invention relates to plier wrenches which are self-locking but which may be readily released from the locking condition. One form of this tool which has been commercially available on the market for a number of years is sold under the trademark VISE GRIP.
While lockable pliers wrenches may be made in different sizes, for practical purposes, any one particular size must exhibit some range of adjustability in order to be able to grip and lock onto objects within a rather wide size range. Accordingly, these tools must incorporate a size adjusting feature to accommodate objects of different sizes within a particular range.
In the VISE GRIP tool, which is perhaps the most popular tool of this general type, object gripping size adjustment is obtained by turning an adjusting screw which moves axially and causes this tool to assume its shortest overall length when it is at the small end of its gripping range and to substantially increase its overall length when adjusted to the large end of its gripping range. Depending upon the dimensions of the particular space in which the tool is being used, the substantial increase in overall tool length may limit the utility of the tool in tight or confined situations.
The object of the invention, generally stated, is the provision of locking pliers wrenches which are adjustable to grip objects in a range of sizes and which are economical to produce from economical components and which has a size adjusting screw which does not move axially in operation.
Certain other objects of the invention will be in part obvious and in part appear hereinafter. For a more complete understanding of the nature and scope of the invention reference may be had to the accompanying drawings in which: